Prediction and monitoring upper-extremity motor recovery after severe stroke. Clinical and neurophysiological studies.

Abstract

Contains fulltext : 40151_predanmou.pdf (publisher's version ) (Open Access)Stroke is an important disease in Western Society with an estimated incidence of 30.000 patients/year in the Netherlands. In approximately 70 to 80% of the stroke survivors upper-extremity motor function is impaired and in almost one third of these patients motor impairments are severe. Among those with severe impairments, two-thirds do not regain the functional use of the affected arm or hand. Nevertheless, nearly 25% of these patients will regain partial motor recovery, and 5-20% even complete motor recovery. These 'recovery' patients, however, cannot be accurately identified by clinical assessment. The pathophysiological processes underlying motor recovery after stroke and the development of spasticity are not well understood. It seems essential to enhance our knowledge of (cortical) reorganization processes to predict motor recovery and ultimately improve the effects of various treatment approaches in stroke patients. Transcranial magnetic stimulation is a non-invasive neurophysiological technique to assess the integrity of the corticospinal pathways both objectively and quantitatively. TMS is particularly effective in the activation of distal hand muscles in which a short-latency motor evoked potential (MEP) can be recorded by surface electromyography. Previous studies consistently showed high specificity of the presence of a MEP (100%) in those patients who will show upper-extremity motor recovery. There is also some evidence that TMS may be of value in predicting the development of post-stroke spasticity through information obtained from the silent period (SP). In this study, both clinical examinations and neurophysiological techniques will be used to investigate the importance of the integrity of the corticospinal pathways for upper-extremity functioning. In particular, the additional predictive value of both MEP and SP to clinical examination with regard to post-stroke hand motor recovery will be determined in patients with a severe, middle cerebral artery stroke. The development of spasticity will be monitored and predicted in these patients as well.RU Radboud Universiteit Nijmegen, 27 mei 2008Promotores : Geurts, A.C.H., Zwarts, M.J. Co-promotores : Pasman, J.W., Hendricks, H.T.191 p